We continue to examine the possible role of genetic susceptibility in the etiology of lung cancer in two distinct studies. The first is a case-control study of African-Americans and Caucasians in Los Angeles County. Subject enrollment (356 cases and 731 control subjects) was completed by S. London while she was a faculty member at University of Southern California. We are currently analyzing data on the combined polymorphisms of GSTT1, GSTM1 and microsomal epoxide hydrolase. In the past year, we published the first report of the relation between lung cancer risk and a genetic polymorphisms of CYP2A6. In contrast to a recent report in nature, we found no association with smoking behavior. We continue to collect the archival tissue on subjects in this study. We also also participating in an international collaborative project to pool original data from studies of genetic polymorphisms and lung cancer risk. The other study is a cohort study of 18,244 Shanghai men (Ronald Ross, USC, PI). The DNA source is from serum presents challenges because of the smaller quantity to compared to buffy coat or whole blood. Laboratory analysis of the GSTT1 and M1 polymorphisms is complete and analysis of the exon 7 polymorphisms of CYP1A1 is nearly complete. Preliminary results were presented at the American Association for Cancer Research annual meeting in 1999. We are also examining the relation between IGF1 and lung cancer risk in the Shanghai cohort. IGF1 has been associated with a number of cancers, including a recent report of an association with lung cancer in a case- control study. Because IGF1 is likely to be influenced by the process or treatment of lung cancer, this association needs to be confirmed in prospective studies such as the Shanghai cohort. - polymorphism African-American susceptibility - Human Subjects